PowerProtect Data Manager: TSDM backup would have periodical slowness

Summary: PowerProtect Data Manager Transparent Snapshots over Transparent Snapshot Data Mover (TSDM) backup would have periodical slowness with big data changes. DD reduction observed between 90-99%. ...

This article applies to This article does not apply to This article is not tied to any specific product. Not all product versions are identified in this article.

Symptoms

  • Protection Mechanism is Transparent Snapshot (TSDM)
  • It is larger than expected data written to PowerProtect DD and often close to the size of the VM disks.
  • Backup shows huge data amounts though there are little to no changes occurring on the VM.
  • 90-99% Reduction rate observed.
  • Backup takes longer than expected intermittently
  • Issue is often observed on a weekly basis

Cause

There are several issues on the VMware LWD side that affect the reported changed data for backup.

PowerProtect Data Manager TSDM uses VMware LWD snapshot and the VM backup type.

  • During a Full Backup, there is an LWD Full sync followed by a Delta Sync for every VM disk.
  • During a Synthetic Full Backup, there is a Delta Sync for every VM disk.

 

https://knowledge.broadcom.com/external/article?legacyId=2150251This hyperlink is taking you to a website outside of Dell Technologies.

Resolution

Workaround:

Option 1: To continue to use PowerProtect Data Manager TSDM.

Disabling unmap/fstrim/trim in the guest OS as per https://knowledge.broadcom.com/external/article?legacyId=2150251This hyperlink is taking you to a website outside of Dell Technologies.

 

Option 2: Switch to PowerProtect Data Manager VADP

If avoid OS-level changes, use VADP Protection Mechanism to back up VMs, bypassing the VMware issue.

Affected Products

PowerProtect Data Manager, PowerProtect Software
Article Properties
Article Number: 000215098
Article Type: Solution
Last Modified: 25 Mar 2026
Version:  4
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